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+
+#ifndef __CPU_OZONE_NULL_PREDICTOR_HH__
+#define __CPU_OZONE_NULL_PREDICTOR_HH__
+
+#include "arch/isa_traits.hh"
+#include "cpu/inst_seq.hh"
+
+template <class Impl>
+class NullPredictor
+{
+ public:
+ typedef typename Impl::Params Params;
+ typedef typename Impl::DynInstPtr DynInstPtr;
+
+ NullPredictor(Params *p) { }
+
+ struct BPredInfo {
+ BPredInfo()
+ : PC(0), nextPC(0)
+ { }
+
+ BPredInfo(const Addr &pc, const Addr &next_pc)
+ : PC(pc), nextPC(next_pc)
+ { }
+
+ Addr PC;
+ Addr nextPC;
+ };
+
+ BPredInfo lookup(Addr &PC) { return BPredInfo(PC, PC+4); }
+
+ void undo(BPredInfo &bp_info) { return; }
+
+ /**
+ * Predicts whether or not the instruction is a taken branch, and the
+ * target of the branch if it is taken.
+ * @param inst The branch instruction.
+ * @param PC The predicted PC is passed back through this parameter.
+ * @param tid The thread id.
+ * @return Returns if the branch is taken or not.
+ */
+ bool predict(DynInstPtr &inst, Addr &PC, unsigned tid)
+ { return false; }
+
+ /**
+ * Tells the branch predictor to commit any updates until the given
+ * sequence number.
+ * @param done_sn The sequence number to commit any older updates up until.
+ * @param tid The thread id.
+ */
+ void update(const InstSeqNum &done_sn, unsigned tid) { }
+
+ /**
+ * Squashes all outstanding updates until a given sequence number.
+ * @param squashed_sn The sequence number to squash any younger updates up
+ * until.
+ * @param tid The thread id.
+ */
+ void squash(const InstSeqNum &squashed_sn, unsigned tid) { }
+
+ /**
+ * Squashes all outstanding updates until a given sequence number, and
+ * corrects that sn's update with the proper address and taken/not taken.
+ * @param squashed_sn The sequence number to squash any younger updates up
+ * until.
+ * @param corr_target The correct branch target.
+ * @param actually_taken The correct branch direction.
+ * @param tid The thread id.
+ */
+ void squash(const InstSeqNum &squashed_sn, const Addr &corr_target,
+ bool actually_taken, unsigned tid)
+ { }
+
+};
+
+#endif // __CPU_OZONE_NULL_PREDICTOR_HH__